OSAGE, Iowa — Time was when Rep. Thomas P. (Tip) O'Neill Jr. was the Democrat whom campaigning Republicans most loved to bash, but these days the retired House Speaker rates a fond and frequent mention from one of the GOP's top presidential contenders.

"Tip O'Neill tells a story that when he first ran he lost," Senate Minority Leader Bob Dole told voters huddled in the Knights of Columbus Hall here the other day.

"But he was thinking about running again, and he was a nice guy so he went around and thanked everybody anyway. Knocked on one door and a lady came out and Tip says, 'Thanks for voting for me.' She says, 'I didn't vote for you.' Tip says, 'Why not?' She says, 'You never asked me.' "

It is not by accident that Dole weaves that anecdote into his chats with voters at almost every stop. O'Neill was the ultimate Capitol Hill wheeler-dealer with the clout, connections and savvy to get things done. And Dole, too, would like to be seen as the same kind of effective insider.

How times have changed on the Republican presidential campaign trail. Ronald Reagan, a stranger to Washington and proud of it, swaggered into the White House vowing to show those in the established political order how to get things done.

This time around, though, Washington experience is considered a big plus by many of the candidates. Both Dole and his chief GOP rival, Vice President George Bush, trade on variations of the theme, with each claiming a lock on the right kind of know-how while dismissing the other's credentials as inferior.

Dole is positively crowing over his credentials as a creature of the same political order that Reagan disdained. Bush, meanwhile, sells himself as a kind of apprentice chief executive in training these last seven years for the real thing.

Sees Pendulum Swinging Back

"I think the pendulum has swung back towards experience, back towards hands-on, back towards working with Congress," Dole told supporters at a campaign coffee in Hooksett, N.H., last Monday.

Dole may share some of the philosophy of Reagan and other new wave conservatives, but unlike them, he is not seeking to depict government as a scapegoat for the nation's ills. Rather, he stresses its vital role in solving problems and shaping the future.

Argues Sen. Warren B. Rudman, Dole's New Hampshire campaign chairman: "What Americans are looking for is someone who understands that government is an entity and it has to be run. My constituents say they don't want an outsider to come in next January and start fighting with Congress immediately."

To some extent, Dole is making a virtue out of necessity. After spending 27 years in the House and Senate, the last three as the most visible and powerful Republican in Congress, he is hardly in a position to pick up on Reagan's confrontational theme.

That explains why the lawmaker bristled so fiercely earlier last week when Bush suggested that Congress was an impediment to solving the budget deficit and other national problems. The vice president was not only ridiculing Dole's life's work, but also assaulting his campaign strategy.

Recites Accomplishments

Talking to voters, Dole regularly recites a laundry list of his proudest legislative accomplishments--indexing tax brackets to shield taxpayers from inflation, a Social Security restructuring to put the system on a sound financial footing, renewal of the Votings Rights Act and the 1985 bill that pumped new subsidies and life into the sagging farm industry.

"Look at the record, not the resume," he urged businessmen in Laconia, N.H., recently in a not-so-subtle dig at Bush.

"I believe I'm the one candidate who can deal with Congress. I know all the members. My word is good. They'll all tell you my word is good--Democrat or Republican. I know all the limits. I know all the tricks."

Ironically, the simmering Dole-Bush feud devolved into an ugly mud-wrestling match by midweek after public suggestions from the vice president's camp that Dole might possibly know a few too many tricks. Bush campaign statements attacked Dole for "cronyism" and "mean-spiritedness" and detailed a list of personal attacks Dole allegedly had leveled in public against his chief GOP rival.

They also referred to newspaper accounts of a still-unresolved influence peddling scandal linking former Dole aides, a $30-million Pentagon contract and a blind trust that until recently held the assets of Dole's wife, former Transportation Secretary Elizabeth Hanford Dole.

Confronts Bush

Dole claimed that Bush was trying to impugn his integrity and angrily confronted the vice president on the Senate floor Thursday. On Saturday, for the second time in as many days, Dole declared the feud over and then took another swipe at Bush.